This invention relates generally to apparatus to assist walking, and more particularly to such apparatus which functions to assist in transportation of carried weight, and/or body weight in the direction of walking, in response to treading.
When a person stands, walks, or runs, the force the foot experiences at the ground is transmitted (less the leg weight) to the hip/leg connection. A strut going from ground (slaved to the foot-shoe location) to the hip joint could take some of the load and thus the person would experience less load on the lower limbs and joints. The upper part of the leg-strut cannot be positioned within certain regions at the hip joint, but in the practical case being. positioned in the near vicinity proves satisfactory. If the operator is carrying a heavy back pack, the upper part of the leg-strut can couple directly to the back pack and, by supporting some or all of the back pack""s weight, decrease the hip joint load.
Further, a person running or walking ordinarily has an unloaded leg and foot, and one loaded leg and foot. The unloaded leg/foot is bent to decrease its length and has the foot off the ground. What is needed is a leg strut on that leg/foot free to vary in its length-without appreciable resistance. Thus the free (unloaded) leg operates as though there were no leg-strut. However, the load on the loaded leg is decreased by whatever amount its leg-strut carries.
It is a major object of the invention to provide struts with lower end portions that couple to legs or feet of a human who is walking or running, or climbing, or descending or jumping down, the upper end portions positioned to a rack or structure secured to the upper body, the struts directly transmitting backpack or backrack loading to the ground, i.e. independently of the carrying force of the user""s legs.
Another object is to provide a load bearing flexible joint connection between the backpack or backrack and the upper end of a strut, and two such joints may be provided, one for each strut. In addition flexible joints may be provided to couple the lower ends of the struts to the user""s shoes or boots.
Another object is to provide a shoe force sensor controlling a lock between relatively movable upper and lower struts, permitting the user""s leg and associated struts to relatively extend or retract freely when the user""s foot is lifted relative to ground so that shoe sole transmission of strut transmitted loading is zero or less than about 3 pounds; and wherein the lock operates to lock against relative shortening of distance between the top and bottom of the upper and lower struts when the user""s leg is vertically loaded to the shoe sole force exceeding about 3 pounds. The lock does not inhibit strut lengthening.
A further object is to provide extensible struts that extend and retract in distance, as in telescoping, or which extend and retract in an articulated or hinged mode.
An additional object is to provide a controlled brake that allows the struts to be retracted against an imposed braking force when the user""s leg is bent or flexed (as at the knee) to an extent that the flexed knee is 1 inch or more ahead of straight leg position.
The following are considerations to be taken into account, or that may be taken into account. The details of the force the foot exerts on the ground throughout a walking or running gait over rough ground are complexxe2x80x94flat foot, mostly heel, mostly toe, heel raised so only front of foot contacts ground, etc. The leg-strut, for simplicity, contacts the ground at only one convenient location, and has some vertical xe2x80x9cslopxe2x80x9d (i.e. looseness) in its vertical connection to the shoe and vertical xe2x80x9cslopxe2x80x9d in its connection to the operator""s body through the backpack rack and the connection of the rack to the body. If the lower strut end connects to the shoe more rearwardly than depicted here, some greater vertical xe2x80x9cslopxe2x80x9d is appropriate so the strut still provides support as the heel is raised while the toe still contacts the ground.
It is another major object of the invention to provide,apparatus to assist human walking or running, that comprises in combination:
a) first and second strut members that are relatively movable, and adapted to support body associated loading, where such loading may comprise loading from a carried pack, from a backpack, or from the human body, or any combination of these,
b) first means to transmit said loading and comprising at least one of the following:
i) a seat,
ii) a rack such as part of a backrack,
iii) a pack, such as part of a backpack,
iv) an attachment connectable to the human body, such as a strap or straps, a harness, or other connection,
v) a hand grip,
vi) a support such as a crutch top,
c) second means to connect the second strut member to foot or ankle apparel such as a shoe worn by the human,
d) and third means to alternately block and unblock such relative movement of the strut members in response to step-by-step treading to assist in transport of said loading in the direction of walking.
It is another object to provide a latching interconnection of the strut upper and lower members, responsive to treading. For this purpose, a ground engaging plate member may be hinge connected (i.e. xe2x80x9cslavedxe2x80x9d) to the user""s shoe, and a link may connect that plate with a latch, to provide latch response to treading.
A further object is to connect the strut upper member with a user""s backpack rack, strapped (i.e. xe2x80x9cslavedxe2x80x9d) to the user""s back, for load transfer purposes. Both left and right strut extensible upper members may be connected to that rack, to directly transfer loading to the ground.
It is a further object of the invention to provide such first means to comprise an attachment to attach to the human body, that attachment having load transfer association with said first member. The attachment is typically configured to attach to the human shoulder area, and may comprise a rack as part of a backpack. The second means may advantageously comprise a bracket adapted for connection to the shoe, the bracket having load transfer association with the second member. Such a bracket may be connectable to a human shoe.
Yet another object is to provide a control to controllably effect alternate blocking and unblocking relative movement of the overall length defined by the strut members in response to such walking. One highly advantageous form of control includes generally longitudinally spaced shoulders such as teeth on one of the members, a shoulder engaging and disengaging part, and a load transfer member that extends generally lengthwise and between said second means (slaved to the foot) and that part.
A further object includes provision of guides on the two longitudinally extending strut members to guide relative longitudinal movement thereof. In this regard the members may have telescopically sliding interfit.